The efficacy of eight plant extracts (garlic, clove, garden quinine, Brazilian pepper, anthi mandhaari, black cumin, white cedar and neem) in controlling leaf rust disease of wheat was investigated in vitro and in vivo. In vitro, all treatments inhibited spore germination by more than 93%. Neem extract recorded 98.99% inhibition of spore germination with no significant difference from the fungicide Sumi-8 (100%). Under greenhouse conditions, seed soaking application in neem extract (at concentration of 2ml/L) resulted in 36.82% reduction in the number of pustules/leaf compared with the untreated control. Foliar spraying of plant extracts on wheat seedlings decreased the number of pustules/leaf. Foliar spraying of plant extracts four days after inoculation led to the highest resistance response of wheat plants against leaf rust pathogen. Spray application of wheat seedlings with neem, clove and garden quinine extracts, four days after inoculation with leaf rust pathogen completely prevented rust development (100% disease control) and was comparable with the fungicide Sumi-8. Foliar spray application of wheat plants at mature stage with all plant extracts has significantly reduced the leaf rust infection (average coefficient of infection, ACI) compared with the untreated control and neem was the most effective treatment. This was reflected on grain yield components, whereas the 1000-kernel weight and the test weight were improved whether under one- or two-spray applications, with two-spray application being more effective in this regard. Thus, it could be concluded that plant extracts may be useful to control leaf rust disease in Egypt as a safe alternative option to chemical fungicides

Nanoparticles (NPs) have attracted great interest in various fields owing to their antimicrobial activity; however, the use of NPs as fungicides on plants has not been sufficiently investigated. In this study, the antifungal activities of sulfur nanoparticles (S-NPs) and copper nanoparticles (Cu-NPs) prepared by a green method were evaluated against Botrytis cinerea and Sclerotinia sclerotiorum. The formation of NPs was confirmed by transmission electron microscopy (TEM) and X-ray diffraction analysis (XRD). The antifungal activities of NPs (5–100 µg/mL), CuSO₄ (4000 µg/mL), and micro sulfur (MS) were compared to those of the recommended chemical fungicide Topsin-M 70 WP at a dose of 1000 µg/mL. They were evaluated in vitro and then in vivo at different temperatures (10 and 20 °C) on cucumber (Cucumis sativus) fruits. The total phenolic content (TPC) and total soluble solids (TSS) were determined to study the effects of various treatments on the shelf life of cucumber fruits, compared to untreated cucumber as a positive control. The diameters of S-NPs and Cu-NPs ranged from 10 to 50 nm, and 2 to 12 nm, respectively. The results revealed that S-NPs exhibited the highest antifungal activity, followed by Cu-NPs. However, CuSO₄ showed the lowest antifungal activity among all treatments. The antifungal activity of the prepared NPs increased with the increase in NP concentration, while the fungal growth was less at low temperature. The cytotoxicity of the prepared NPs was evaluated against the WI-38 and Vero cell lines in order to assess their applicability and sustainability. S-NPs caused less cytotoxicity than Cu-NPs.